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Note 4 - Cash and Cash Equivalents and Short-term Investments (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Cash, FDIC Insured Amount | $ 2,700,000 |  |
Short Term Investments Maturity | 90 days |  |
Available-for-sale Equity Securities, Amortized Cost Basis | 48,100,000 | 44,300,000 |
Proceeds from Sale of Available-for-sale Securities | 26,661,000 | 101,415,000 | 140,493,000
Available-for-sale Securities, Gross Realized Gains |  | 390,000 |
Available-for-sale Securities, Gross Realized Losses | 0 | 388,000 |
Available-for-sale Securities, Gross Unrealized Gain (Loss) | 1,100,000 | 372,000 |
Investment Income, Interest | 1,300,000 | 1,700,000 | 1,800,000
Cash Equivalents [Member] |  |  |
Available-for-sale Securities, Gross Realized Gains | 785,000 |  |
Municipal Bond Securities [Member] |  |  |
Available-for-sale Equity Securities, Amortized Cost Basis | 20,500,000 | 19,400,000 |
Majority Owned Joint Ventures [Member] |  |  |
Restricted Cash and Cash Equivalents | $ 980,000 |  |

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